A wide variety of systems have been developed for the recording and playback of text and audio, intermixed on the same recording media. For the most part, these systems have involved the use of playback equipment that is modified in design from the widely disseminated consumer audio tape cassette and compact disk (CD) players. Hence, in order for a consumer to make use of these prior art systems, new player equipment must be purchased, along with specially recorded media which is generally not compatible with the consumer's existing equipment.
There are several consumer electronics applications for recorded media in which text is intermixed with audio selections. One such application is karaoke, where the user sings the lyrics of a song in synchronism with an audio orchestration of the song. A second such application is referred to as "sing-along," where the user sings the lyrics of a song along with a pre-recorded vocal arrangement. In both the karaoke and sing-along applications, it is desirable to display the song lyrics in synchronism with the orchestral or vocal arrangement.
Another application is in programs for learning a foreign language, and in language translators. In such programs, it is desirable to display the text representation of a foreign language word or phrase, while the user listens to the audio pronunciation of that word or phrase in the foreign language. Yet another application is to identify in text form identifying information relating to a musical selection, such as the name of the selection, the artist name, composer, album name, etc. Still another application relates to radio broadcasts, where it is desirable to display to a user in text form information which supplements audio advertisements and editorials.
Many existing video systems presently provide karaoke and sing-along, where the lyrics to the song being played are recorded on, for example, video tape. The lyrics are recorded on the video portion of the video tape in a manner similar to the recording of other video images. The lyrics may be superimposed over a television image of the performers of the music, such as a music video, or over other artistic video creations. Similarly, video disks may contain karaoke and sing-along lyrics. As with video tape, the lyrics may be recorded along with other video information. Video disks, also referred to as laser disks (LD), store the lyrics and other video information digitally.
Another system has been developed for using standard audio tape players, such as standard cassette tape recorders, in conjunction with specially recorded audio tape to assist the user in karaoke and sing-along. In the way of background, consumer magnetic audio tape is divided into two longitudinal regions on the tape. One region of the tape is for recording and playing music when the tape is moving in one direction and the other region is for recording or playing music when the tape is moving in the opposite direction. In stereo systems, each region is divided into two spaced-apart longitudinal tracks for recording music for the left and right channels of a stereo recording. The special audio tapes for karaoke and sing-along applications have orchestral arrangements of a song recorded in the left channel and accompanying vocals in the right channel. The singer may either sing along with the singer recorded on the tape or sing solo by playing (using a balance control) only the music recorded on the left channel. Alternatively, the vocals may be provided to headphones so that only the singer hears the vocals, which allows the singer to be able to sing along with the recorded vocals without the audience hearing them. The singer reads the lyrics from printed text provided with the tapes.
Another prior art system for use in karaoke applications is known as CD+G (CD plus graphics). In this system, a special CD player must be purchased, along with special CD+G disks. The CD+G disks have encoded thereon in digital form the lyrics which accompany orchestral arrangements which are also encoded on the disk. The special player separately decodes the lyric data, converts it into a standard NTSC television video signal, and provides it to a video output connector. The audio data on the disk is provided to conventional stereo audio output connectors. In use, the video output signal is provided to the video input terminal of a television receiver, and the audio output signals are provided to headphones or a stereo audio system. When the CD+G disk is played, the audio orchestration of the song is heard, and the lyrics appear on the television screen in synchronism therewith.
For radio broadcast applications in which text is intermixed with audio programs, a system known as RDS (radio data system) has been developed, and is in widespread use in Europe. In this system, special FM receivers are required to receive an FM subcarrier signal carrying a digital representation of broadcast text messages, which are displayed on a receiver display. Special subcarrier equipment is required at the broadcast station to accomplish this function. No known comparable system exists for use with AM broadcasts.
While AM and FM broadcast station program materials generally consist of a combination of music, news, advertising, and information programs, the interest of a large segment of the listening audience is directed to the music portion of the broadcasts. In fact, the music industry cooperates with the radio stations and encourages the broadcast of the latest album releases on the basis that most album sales are the result of audience reaction to broadcast musical selections.
One of the more frustrating aspects confronting the listener concerns deciphering the lyrics of music selections received on the radio. Often the lyrics of vocal music, from modern popular music to classical music, are difficult to understand, even after the selection is heard many times. It is sometimes possible for a listener to obtain lyrics by buying the compact disc (CD) on which the selection is included. However, many compact discs do not include printed lyrics and the listener has no way to know before buying the CD whether lyrics are included. Further, the listener must buy the whole CD on which the selection is included just to get the lyrics of the one desired selection.
Even if printed lyrics are obtained by the listener, the printed lyrics do not indicate when the individual words are sung in relation to the music contained on the CD. One way of solving this problem are the video sing-along systems and "karaoke" systems described above. However, these self-contained systems reproduce musical selections, often with the lead vocal omitted and display lyrics on video screens. In addition, these systems involve expensive equipment and require the additional purchase of special recordings of musical selection that often can be only used with the sing-along systems.
Another source of frustration is the identification of the broadcast musical selections, particularly since the stations do not employ a uniform method of identification. Some stations announce the titles of a group of selections prior to their broadcast, others announce the titles after the broadcast of such a group, while still others provide such announcements on a random basis. Rarely do the stations announce the title, artist and album information for each selection. The result is that the listener is generally unable to rapidly identify and remember a particular musical selection with sufficient accuracy to enable the subsequent purchase of the album containing that selection.